How India can claim being Polio-free ?

India will on Monday be accorded “polio-free” status by the World Health Organization (WHO), with not a single case of the crippling disease being reported in the past three years, but studies show the alarming rise of another similar paralytic condition that experts suspect may be a result of increased dosage of polio drops.

The last case of polio in the country was reported on 13 January, 2011, from West Bengal. Following the “polio-free” status, India will be certified as a polio-free nation by March, leaving Afghanistan, Pakistan and Nigeria as the remaining polio endemic countries.

India’s dramatic turnout in polio eradication, though, has seen a consistent sidelining of the increasing incidence of non-polio acute flaccid paralysis (NPAFP) cases. In the last 13 months, India has reported at least 53,000 cases of NPAFP.

Many health activists say the government, in its rush to get the polio-free certification for the country, ignored the increasing incidence of NPAFP.

Acute flaccid paralysis (AFP) is a condition in which a patient suffers from paralysis that results in floppy limbs due to reduced muscle tone. While AFP is symptomatic of polio, it can be caused by other diseases such as the Guillain Barre Syndrome and nerve lesions as well—the primary cause fuelling the argument that India is not really free of wild polio virus.

Highest NPAFP rate

Government surveillance data show that while India is set to be tagged as polio-free, it has actually become the nation with the world’s highest rate of NPAFP incidence.

In the past 13 months, India has reported 53,563 cases of NPAFP at a national rate of 12 per 100,000 children—way above the global benchmark set by WHO of 2 per 100,000. WHO data indicate NPAFP cases have been increasing steadily since 2003, when the number was at 8,000.

In 2004, 12,000 cases of NPAFP were reported in the country, increasing dramatically to 25,000 in 2005. In 2007, the number crossed 40,000 and in 2011 the year India reported its last polio case—nearly 61,000 children were detected to be suffering from NPAFP.

“The increased number of non-polio AFP cases being investigated by the national polio surveillace programme (NPSP) has been due to an increased reporting of AFP cases following deliberate efforts made by the programme to increase the sensitivity of the surveillance system in order to reduce the risk of missing any polio cases,” said Nata Menabde, WHO representative to India. “The intensity of these actions was monitored very closely in UP (Uttar Pradesh) and Bihar—the two traditional polio reservoir states—to ensure no polio cases gets missed in these states,” she added.

Two doctors from Delhi’s St Stephens Hospital, Neetu Vashisht and Jacob Puliyel, who compiled data from the national polio surveillance project, found a link between the increase in dosage of polio vaccination and the increasing cases of NPAFP.

“Most experts will tell you the cases of NPAFP have increased because of better surveillance. This is bunkum,” said Puliyel. “As per global benchmarks, as polio incidence comes down, the rate of NPAFP should also reduce. Instead, AFP cases have been increasing steadily.”

“In 2010, the government reduced the number of pulse polio doses from 10 to 6. What we found was that between 2010-2013, the number of APF cases also came down. Our paper argues that other kinds of polio are being caused by the excessive administration of polio dosages,” Puliyel said. “Another proof is that states like Kerala and Goa, where dosages were less, AFP cases was also less. Majority of NPAFP cases are reported from Bihar and UP, where several immunization rounds are held to reach universal coverage. These are figures the government does not want to admit.”

The health ministry has denied NPAFP is rising, stating that the increasing numbers are indicative of good government surveillance. This, however, does not explain why a majority of the NPAFP cases are found in Uttar Pradesh and Bihar. UP and Bihar have an annualized NPAFP rate of 21 per 100,000 children and 34 per 100,000 children, respectively.

“Our surveillance is very sophisticated and the incidence has gone because every case is being picked up. Even at the least bit of suspicion, we report the case because we want to ensure it is not a polio case,” said Anuradha Gupta, additional secretary, health ministry. “One must also keep in mind that AFP can actually result due to various reason other than polio.”

Polio’s global resurgence

“Even if the polio-free certificate was a legitimate success, it is just that—a certificate,” said Deepak Kapoor, head of Rotary International’s national pulse polio committee.

Since 2005, there has been a resurgence of polio in Syria, Egypt, Tajikistan and Israel. So, while India is celebrating the success of its polio campaign, the threat of a resurgence is ongoing and real, Kapoor said.

“This polio-free target was considered impossible a few years ago. Yes, everyone is aware polio is not gone forever, especially because India is yet to achieve 100% immunization and our routine immunization is still poor,” he added.

“Having said that, if India does not report a case until the end of March, South East Asia Region (SEARO) will be polio free and that is something to celebrate. The certificate, however, is a piece of paper. There are huge risks of importation as many countries like Syria, China, etc., have seen before us. We need to guard against that… The best defence is to reach out and immunize every child in India. Supplementary immunization has to be kept up until our routine immunization is up to the mark,” Kapoor said.

Gupta of the health ministry said: “India has become the first country to issue travel advisory concerning importation. Having said that, the WHO certification will not be affected by re-importation as it is about not having indigenous wild polio virus in the environment.”

India’s strategy to maintain its polio-free status involves phasing out the oral polio vaccine (OPV) due to adverse effects. To contain the “wild” polio virus, OPV uses viruses which are “attenuated” but still alive. This weakened version of polio virus activates an immune response in the body.

The India expert advisory group on polio has recommended that the country’s immunization programme switch from trivalent oral polio vaccine and only rely on the oral bivalent variant, reducing chances of vaccine derived polio virus infection. The switch will be accompanied with a booster shot of injectable polio vaccine. The WHO strategic advisory group of experts (SAGE) on immunization has called for a global, coordinated withdrawal of type 2-containing OPV by the end of 2016, and switch to bivalent OPV.